As is well known, it is desirable to reduce or prevent heat strain in individuals due to the accumulation of metabolic and/or external heat in certain circumstances. Military aircrew, in particular, require various types of protective equipment and clothing (i.e. counter pressure, immersion, chemical defense) that can inhibit adequate dissipation of body heat, even in a conditioned aircraft environment. Such clothing is often referred to as micro-climate conditioning clothing.
Liquid cooling vests have previously been provided for aircrew but some models have had disadvantages. The performance thereof has been dependent on good contact between the vest and the body and this has been difficult to ensure and can vary with body movement.
Furthermore, in prior vests flow of the cooling liquid can be reduced or stopped by a "kink" in one of the flexible members forming a flow path in the vest. Prior air vests have had difficulty in directing cooling air so that it flowed across the body. Instead, the cooling air moved away from the body immediately after reaching a respective distribution site.
Consequently, only a portion of the cooling potential of the air was used so that the performance was low or the flow rate had to be higher than might otherwise be required in order to achieve the desired cooling effect.
It is an object of the present invention to provide heat control means in which the above-identified disadvantages are substantially reduced or obviated.